Two-dimensional gel electrophoresis of dog crevicular fluid proteins

The ligature-induced periodontitis model was used in beagle dogs to compare and contrast profiles of crevicular fluid (CF) proteins collected from gingivitis and periodontitis sites. The protein profiles of CF and serum were determined by 2-dimensional gel electrophoresis (2-D PAGE) using a silver stain. 2-D PAGE showed that CF contained proteins with molecular weight 16 K or less and many proteins with molecular weights between 64 K and 16 K in the isoelectric pH between approximately 5.8 and 6.8. The number of such proteins was greater in samples collected from the ligated (periodontitis) side compared to the non-ligated (gingivitis) side. Thus, analysis by 2-D PAGE revealed differences between CF samples from gingivitis and ligature-induced periodontitis sites. This study suggests that analysis of human CF by 2-D PAGE may be useful in diagnosis and investigation of the pathogenesis of periodontitis.     

Klippel-Feil syndrome: a case report and current understanding of molecular genetic background

A case of Klippel-Feil syndrome in a 12-year-old boy presentingwith the features of low set posterior hairline, short webbed neck, scoliosis and Sprengel's deformity associated with upper eyelid coloboma and pre-auricular appendages is described. Radiologically there was evidence of maldeveloped cervical and upper thoracic vertebrae associated with elevated scapula. The association of the eyelid defect and pre-auricular appendages has not been documented in the past. The current literatures based on the recent advances in understanding of molecular genetic control over embryonic development of the cervical spines were reviewed.     

Effect of extrusion cooking on anti-nutritional factor tannin in linseed (Linum usitatissimum) meal

Primary objective Various oilseeds and their by-products usually constitute a major source of dietary protein as aquafeeds for warmwater herbivorous/omnivorous fish species. The oilseed meals available in India are fairly rich in protein and most of them are traditionally used as valuable feed for farm animals. However, among the factors that limit incorporation of these ingredients in aquafeeds are amino-acid imbalance and presence of anti-nutritional factors. Enhancement of the nutritive value of these ingredients and reduction (or removal) of anti-nutritional factors can be attempted by processing so as to increase the bio-availability of these nutrients. It has been found that various anti-nutritional factors can be destroyed by the process of extrusion cooking. Extrusion is a process whereby raw feed material is exposed to controlled conditions of high temperature, pressure and moisture. In the present experiment, extrusion cooking is used to reduce the anti-nutritional factor tannin in linseed (Linum usitatissimum) meal.

Research design A single-screw cooking extruder, designed and manufactured at the Indian Institute of Technology, Kharagpur, was used for the study. Experiments were carried out following a rotatable central composite design to determine the optimum values of the process variables for which maximum reduction of tannin (Y) occurs. The process variables selected for the study were: barrel temperature (X₁) (60–100°C), extruder speed (X₂) (60–100 rpm) and oilseed moisture content (X₃) (30–50%). Following the design, a second-order response model was fitted.

Main outcomes and results The optimized values of the process variables were found to be X₁=82.5°C, X₂=90 rpm and X₃=41.22%, and the value of the predicted response (i.e. reduction of tannin Y) was found to be 61.25%.     

Expressing collective voices on children’s health: photovoice exploration with mothers of young children from the Indian Sundarbans

Background

The Indian Sundarbans is marked by inhospitable terrain and frequent climatic shocks which jointly hinder access to health care. Community members, and women in particular, have few means to communicate their concerns to local decision makers. Photovoice is one way in which communities can raise their local health challenges with decision makers. This study unlocks mothers’ voices on the determinants of their children’s health to inform local level decision-making on child health issues in the Indian Sundarbans.

Methods

Photovoice action research was conducted in three blocks in the Sundarbans region of West Bengal, India. The project involved eight groups of eight to ten mothers who had at least one child below 6 years of age across four villages. The mothers received training on photo documentation and ethical concerns before taking two rounds of photographs within 6 months, interspersed by fortnightly group meetings facilitated by researchers. Photographs and key messages were communicated to local decision makers during block and village level interface sessions with the mothers and researchers.

Results

Mothers’ photos focused on specific determinants of health, such as water and sanitation; health status, such as malnutrition and non-communicable diseases; service accessibility; climate conditions; and social issues such as early marriage and recurrent pregnancy. Some issues were not captured by photos but were discussed in group meetings, including domestic violence and the non-availability of medical practitioners. We found differences by mother’s educational status, livelihood and caste identity in the extent and nature of photographs taken. As a result of the mother’s interface with community decision makers, which included showcasing a selection of their photos, efforts to improve road infrastructure and human resource availability in the primary health centres and local government were realized.

Conclusion

Photovoice has the potential to express the voices of vulnerable communities regarding their health needs and can help them dialogue with local decision makers to inform community health policy and planning. More needs to be done to understand how social differences among photovoice participants influences how they engage with the methodology.

     

Carbon substitution for oxygen in silicates in planetary interiors

Amorphous silicon oxycarbide polymer-derived ceramics (PDCs), synthesized from organometallic precursors, contain carbon- and silica-rich nanodomains, the latter with extensive substitution of carbon for oxygen, linking Si-centered SiO_xC_4-x tetrahedra. Calorimetric studies demonstrated these PDCs to be thermodynamically more stable than a mixture of SiO₂, C, and silicon carbide. Here, we show by multinuclear NMR spectroscopy that substitution of C for O is also attained in PDCs with depolymerized silica-rich domains containing lithium, associated with SiO_xC_4-x tetrahedra with nonbridging oxygen. We suggest that significant (several percent) substitution of C for O could occur in more complex geological silicate melts/glasses in contact with graphite at moderate pressure and high temperature and may be thermodynamically far more accessible than C for Si substitution. Carbon incorporation will change the local structure and may affect physical properties, such as viscosity. Analogous carbon substitution at grain boundaries, at defect sites, or as equilibrium states in nominally acarbonaceous crystalline silicates, even if present at levels at 10–100 ppm, might form an extensive and hitherto hidden reservoir of carbon in the lower crust and mantle.The carbon cycle is one of the most important components in the sustenance of life and the evolution of the environment on our planet. The exchange of carbon between the atmosphere, biosphere, and oceans primarily controls the near-surface carbon cycle in the short term (decades to millennia) (1, 2). However, a large fraction of the carbon in the planet is stored at a greater depth (i.e., in the crust, mantle, core), and it exchanges with the surficial carbon only on much longer time scales (millions of years) through processes involving subduction and volcanic activity (3, 4). The form of stored carbon in these deep reservoirs and the amounts of carbon in various reservoirs, as well as the balance between the inward and the outward fluxes of carbon from them, are poorly constrained (3, 4). In the crust and upper mantle under relatively oxidizing conditions, CO₃²⁻ provides the familiar trigonal (sp²) coordination environment for carbon in carbonates, mixed CO₂-H₂O fluid phases and carbonatite-forming melts. Under more reducing conditions, graphite, diamond, and methane become important and carbonate becomes less important or absent. The substitution of tetrahedral (sp³) carbon for silicon in silicate minerals and melts has often been suggested as a possibility at high pressure (5–13), but there was little experimental evidence for it until recent phase equilibrium studies indicated that CO₂ can undergo transformation from a molecular gas to an extended solid at very high pressure and temperature to form a cristobalite-like structure consisting of a network of corner-sharing CO₄ tetrahedra (13, 14). Recent studies have also indicated the possibility of a chemical reaction between SiO₂ and CO₂ to form a silicon carbonate phase under pressure (12) and the possibility of amorphous solid phases (7, 11). However, the experimental results and their structural interpretations have remained somewhat controversial, and, in any event, such reactions appear to require pressures near a megabar, probably making them unimportant for most of the crust and mantle.Here, we propose an alternate and facile mode of carbon incorporation into silicates in the crust and mantle under moderately reducing conditions, namely, its substitution not for silicon but for oxygen in a silicate tetrahedron. This mechanism of substitution is well documented in so-called “polymer-derived ceramics” (PDCs; recently reviewed in ref. 15), X-ray amorphous but nanoheterogeneous solids in the Si-C-O system that are prepared over a wide range of compositions via pyrolysis of organometallic polymer precursors (Fig. 1 A and B). Their nanostructure, characterized extensively by solid-state NMR and other spectroscopic techniques, small angle X-ray scattering, and transmission electron microscopy, consists of interconnected domains of relatively disordered sp² carbon layers (ranging from graphene sheets to turbostratic graphite) and amorphous silica-rich regions (Fig. 1C). The latter are not pure SiO₂ but contain several percent carbon, which substitutes for oxygen in the tetrahedra, forming a mixture of SiO₄, SiO₃C, SiO₂C₂, SiOC₃, and SiC₄ species (15). Because all these silicon-centered tetrahedra are bonded through their oxygen and carbon atoms to the neighboring tetrahedra, the network remains fully connected by corner sharing. Indeed, the carbon tends to bond to four silicon atoms (and not to oxygen), whereas oxygen bonds to two silicon atoms; thus, the network is even more cross-linked, making local structure different and somewhat heterogeneous on the nanometer scale (15). Nevertheless, the structure can be considered to be a new amorphous phase with a high concentration of mixed-bond tetrahedra and not an intergrowth of separate silicon carbide and silicon oxide nanophases. The absence of carbon-oxygen bonds in these structures argues against carbon incorporation as a species related to CO or CO₂.Open in a separate windowFig. 1.Polymer-derived SiOC ceramics: synthesis by the pyrolysis of polysiloxanes (A), composition diagram (B), and nanodomain structure and silicon coordination in the ceramic state (C).It has been established that these SiOC PDCs are stable energetically (and presumably in free energy as well, because they are disordered) with respect to a mixture of SiO₂ (glass or cristobalite), C (graphite), and silicon carbide (SiC) (15). This is a critical observation for the present argument because such thermodynamic stability suggests that although the organometallic precursor route may be kinetically necessary to overcome barriers to synthesize SiOC ceramics at atmospheric pressure and at low enough temperatures to avoid carbothermic reduction of silica by graphite by the reaction SiO₂ + 3C = SiC + CO (gas), it may not be thermodynamically necessary and the SiOC materials may not be metastable because they are favored by both energetic and entropic (disorder) factors. Furthermore, pressure of even 1 GPa will strongly disfavor carbothermic reduction and extend the stability field of the SiOC materials. This is because the driving force in the free energy for such reduction is the large positive entropy (and volume) increase in forming gaseous products. At pressures of roughly 1 GPa and above, the molar volume of CO (and CO₂) is more like that of a liquid or solid (tens of cubic centimeters per mole rather than tens of liters), and the entropy has likewise diminished greatly. Indeed, the major effect on raising the temperature of the reduction reaction will occur in the low-pressure range, where the volume of the products is decreasing most rapidly. This argument will continue to hold, with minor changes in slopes of free energy curves, if phase transitions occur (e.g., graphite to diamond, dense CO or CO₂ fluids to more polymerized phases). Indeed, it has already been shown that SiOC PDCs at moderate pressures of ∼20 MPa can withstand temperatures as high as 1,600 °C (16, 17). Thus, we hypothesize that given the high temperature and pressure, long time scale for chemical reaction, and relatively low oxygen fugacity characteristic of the lower crust and mantle, substitution of carbon for oxygen may be a viable mechanism of carbon incorporation into molten, glassy, and perhaps even crystalline silicates, as well as into grain boundaries.Realizing that the silicate network in minerals and melts is often partially depolymerized with charge balance largely involving aluminum, iron, and alkali and alkaline earths, we must ask whether this mode of carbon incorporation can be maintained in less polymerized environments. Here, we present the results of a structural study of alkali (Li)-containing Si-O-C ceramics that confirm and provide insight into this mechanism of incorporation of C in silicate structures. A multinuclear (⁶Li, ¹³C, and ²⁹Si) NMR spectroscopic approach was taken to investigate the local structure and bonding around Li, C, and Si atoms to obtain a comprehensive structural picture of these materials.The Li-SiOC sample was synthesized via pyrolysis of preceramic organic-inorganic hybrid polymers (Materials and Methods). Chemical analyses indicated a composition of SiLi_0.52O_2.50C_0.84. Powder X-ray diffraction (XRD) (Fig. S1) confirmed the predominantly amorphous nature of the material with a small fraction of Li₂SiO₃ nanocrystallites dispersed in the amorphous matrix. The ²⁹Si magic angle spinning (MAS) NMR spectrum of the Li-SiOC sample is shown in Fig. 2A. It contains multiple broad peaks centered at chemical shifts of around −110, −100, −91, −64, and −21 ppm and a relatively sharp peak centered at −75 ppm. The latter can be readily assigned to the presence of a small amount of Li₂SiO₃ crystals (18), consistent with the powder XRD result. The broad peaks at −110 and −100 ppm can be assigned to various tetrahedral SiO₄ environments typical of glassy silicates that are usually denoted as Qⁿ species, where n denotes the number of bridging oxygens (BOs) that are shared between two SiO₄ tetrahedra. The peaks at −110 and −100 ppm are characteristic of Q⁴ environments bonded to other Q⁴ and Q³ species, respectively (19). The ²⁹Si isotropic chemical shift for SiCO₃ tetrahedra with three BOs and one bridging carbon nearest neighbors is typically located near −71 ppm in Li-free SiOC ceramics (20). Therefore, it is reasonable to assign the major peak at −64 ppm to SiCO₃ tetrahedra with one or two nonbridging oxygens (NBOs). This species is denoted as Q^NBO-C in the subsequent discussion. The presence of the Q^NBO-C species implies depolymerization of the SiOC network due to the addition of an archetypal modifier oxide, such as Li₂O. Because the NBO on this species is expected to be bonded to the Li⁺ ions, it also suggests a close spatial association of Li with C atoms in the structure. Finally, the broad peak at −21 ppm can be assigned to SiC₄ tetrahedra in the network. Simulation of this spectrum with Gaussian line shapes and assuming that the Q^NBO-C species contains 1 NBO atom yields the following relative fractions (atom %) of various Si species: 53% Q⁴, 36% Q^NBO-C 6.4% SiC₄, and 4.6% Q² in crystalline Li₂SiO₃, leading to overall NBO per Si atom, NBO/Si = 0.45, consistent with the chemical composition of the sample characterized by a Li/Si ratio of ∼1:2.Open in a separate windowFig. 2.(A) ²⁹Si MAS NMR spectra of Li-SiOC-700. The experimental spectrum is shown as the bold black line (Top), the simulation is shown as the bold dashed line (Middle), and the individual peak components are shown with thin solid lines (Bottom). (B) ¹³C MAS NMR spectrum of Li-SiOC-700. (C) ⁶Li MAS NMR spectrum of Li-SiOC-700. The ⁶Li NMR chemical shift ranges characteristic of 4-, 5-, and 6-coordinated Li in oxides, as reported in the literature (20), are shown.The ¹³C MAS NMR spectrum (Fig. 2B) consists of two well-resolved but relatively broad peaks at ∼120 and −3 ppm. The former peak can be readily assigned to sp²-bonded carbon environments as in amorphous or turbostratic graphite. On the other hand, the latter peak with a ¹³C isotropic chemical shift of −3 ppm represents sp³-bonded carbon sites in SiC. ¹³C NMR signals corresponding to these two C environments have also been reported in the literature for Li-free Si-O-C samples (20), although in those cases, the ¹³C isotropic chemical shifts for the sp² and sp³ sites are shifted to somewhat higher frequencies (∼140 and 12 ppm, respectively).The ⁶Li MAS NMR spectrum is shown in Fig. 2C. The isotropic chemical shift of the ⁶Li resonance (−0.85 to −0.95 ppm) indicates that the majority of the Li⁺ ions are in sixfold coordination with oxygen (21). The chemical shift range spanned by the ⁶Li MAS NMR spectrum also suggests that Li-C bonding in the PDC would be unlikely because such resonances are expected to be shifted significantly to higher frequencies (22).Based on these observations, we suggest that the substitution of C for O in silicate tetrahedra must be considered as a significant possibility for the interior of the Earth and other planets. Such modes of carbon incorporation include (i) formation of Si–O–C networks characterized by corner-shared SiC_xO_4-x tetrahedra without any C-O and C-C bonding, where C and O atoms are only bonded to four and two Si atoms, respectively, and (ii) formation of a depolymerized Si-O-C network upon incorporation of modifier cations, such as alkali and alkaline earths, where the SiC_xO_4-x tetrahedra may contain one or more NBOs. These structural scenarios are shown schematically in Fig. 3. Although these modes of carbon incorporation can be easily envisaged for amorphous or liquid silicates (magmas), chemical substitution of O by C in a crystalline silicate would require the formation of local defect structures either in the interior of a crystal grain or near grain boundaries and would likely involve significant local rearrangement of the lattice. A schematic representation of one such possible substitution is shown in Fig. 4 for the MgSiO₃ chain silicate structure, where two BO atoms in two Q² chains are replaced by an sp³ carbon atom, resulting in local cross-linking of the two chains.Open in a separate windowFig. 3.Schematic representations of the local structural scenarios corresponding to the various modes of carbon incorporation via substitution of oxygen in silicate structures. (A) SiOC networks characterized by corner-shared SiC_xO_4-x tetrahedra without any C-O and C-C bonding. (B) Depolymerized SiOC network formed from addition of modifier cations, such as alkali and alkaline earths, where the SiC_xO_4-x tetrahedra may contain one or more NBOs.Open in a separate windowFig. 4.Schematic representation of a “defect” created by the replacement of oxygen by carbon in the lattice of an ortho-enstatite (MgSiO₃) structure. The Si, O, Mg, and C atoms are shown in yellow, red, green, and dark gray, respectively. The chains of Q² SiO₄ tetrahedra in the structure are oriented along the crystallographic c axis indicated by the arrow. Two BO atoms connecting two pairs of SiO₄ tetrahedra in the neighboring chains have been substituted by the carbon atom that now bonds to four Si atoms (shown in pink) and cross-links the two chains. This substitution results in the formation of four SiO₃C tetrahedra, as shown. Although not shown here, the structure near the defect is expected to relax in response to this substitution.Annealing the Li-SiOC sample at a higher temperature (1,100 °C) caused extensive crystallization of lithium silicate and apparent disruption of the Si-O-C network. Differential scanning calorimetry showed only a strong crystallization exotherm above 800 °C with no evidence of a glass transition in the amorphous Si-O-C domains. No mixed bonded tetrahedra in the crystalline lithium silicate phases could be detected by NMR, although such substitution at trace levels, below a few percent, would not be easily detected. Thus, the extent of substitution of carbon for oxygen in crystalline silicates remains open. However, even if this substitution occurs at a low level (e.g., on the order of 10–100 ppm), the large volumes of silicates resident in the lower crust and mantle would provide an extensive “hidden” reservoir for carbon in nominally acarbonaceous phases, analogous to that of H₂O in nominally anhydrous phases as discussed extensively in the recent literature (23). If melts (magmas) in contact with graphite (and in the absence of significant carbonate) or amorphous phases in grain boundaries are also present, this reservoir could be greatly enhanced.It is not yet possible to quantitate the extent and importance of such a reservoir both because the degree of carbon incorporation by this mechanism in natural systems is not yet known and because the carbon inventory of the lower crust, mantle, and core is poorly constrained (4). However, one should note that a low level of substitution would decrease the thermodynamic activity of the C (or SiC) component in the solid or liquid phase where carbon occurs. As an example, if the carbon activity (similar to or likely smaller than its concentration) is 10⁻³, the oxygen fugacity for oxidation to CO₂ by the reaction C (in solid or melt) + O₂ = CO₂ would be increased by three orders of magnitude. This would extend the oxygen fugacity range over which such carbon incorporation could occur, at low concentration, to more common mantle conditions. Thus, some trace carbon incorporations into silicates by this mechanism could occur at oxygen fugacities higher that those needed to maintain silicon carbide, graphite, or diamond. Of course, at the upper end of the oxygen fugacity range, carbon incorporation by CO₂ (and/or CO) solubility will become dominant. Furthermore, considering the strongly reducing conditions likely to have existed in the Hadean era, including the period of core formation and several possible magma ocean episodes (24), the proposed mechanism of carbon incorporation may have been more widespread in primordial times and could have played an important role in setting the carbon inventory of the crust, mantle, and core. The major hypothesis of this paper is simply that such a mechanism of incorporating carbon in silicates merits further consideration by both experimental and theoretical approaches.     

Pregnancy Complicated by Maternal Heart Disease: A Review of 281 Women

Objectives

To study maternal heart disease in an Indian setting for: (1) different etiological factors, (2) different types of lesions, and (3) maternal and perinatal outcome.

Methods

281 women with heart disease who delivered ≥28 weeks of gestation at different teaching institutions (tertiary care centres) in India were studied.

Results

Rheumatic heart disease (n = 195; 69.4 %) with isolated mitral stenosis (n = 75; 26.7 %) were the commonest. Septal defect (n = 27; 9.6 %) was the predominant lesion among the congenital heart disease (n = 60; 21.3 %) patients, whereas in the miscellaneous group (n = 26; 9.2 %), ischemic heart disease (n = 10; 3.6 %) was the leading cause. Multiple cardiac lesions were also diagnosed in 100 (35.58 %) women. In 87 (31 %) women, diagnosis was made first time in labor. Majority n = 131, (46.6 %) had spontaneous vaginal delivery and few (n = 9; 3.3 %) required induction of labor. Cardiac complications were noted in 72 women (25.6 %). There were three (1.06 %) maternal deaths and perinatal mortality was 4 % (n = 11).

Conclusion

In this study, rheumatic heart disease in pregnancy is still predominant though acquired cardiac lesions are rising. In rheumatic heart disease, mitral valve involvement was the commonest and multiple valve lesions were a major observation. Most common obstetric complication was small for gestation baby. Maternal morbidities in the unbooked women are high and congestive cardiac failure was the major cardiac complication.     

Good Research Practices for Measuring Drug Costs in Cost Effectiveness Analyses: An Industry Perspective: The ISPOR Drug Cost Task Force Report—Part V

Objectives:  The industry perspective on drug costs should be framed by the need for decision-makers to use actual and relevant costs, and to inform real-world decisions regarding medication selection and use. The objective of this report is to provide guidance and recommendations on how manufacturers should approach the use of drug costs.
Methods:  The Task Force was appointed with the advice and consent of the ISPOR Board of Directors. Members were experienced developers or users of drug cost information working in academia and industry, and came from several countries. Following the core assumptions developed and outlined by the Task Force, a draft report was prepared. Comments were solicited on the outline and several draft reports both from a core group of external reviewers and more broadly from the ISPOR membership of ISPOR via the ISPOR Web site.
Results:  The industry should always strive for: 1) a focus on drug value and not just cost; 2) credibility—that is correct and consistent costs; 3) transparency—by disclosing the prices and costs, and ensuring that they reflect the actual cost of the drug whenever possible; and 4) providing actionable results that help customers comprehend the value offered by a drug therapy and to use products more efficiently and effectively.
Conclusions:  Understanding and accounting for all costs and consequences of the use of a medical treatment is in the best interests of all parties involved in the prescribing, consuming, reimbursement, selling, and manufacturing of bio/pharmaceuticals. Transparency, consistency, and clear communication of costs and value are essential for appropriate decision-making and should be important goals for all parties.